A woman's ovaries must regularly produce good-quality eggs. Normal sperm must be produced in high enough quantities and be delivered through natural intercourse. The reproductive passageways must be clear for sperm to enter the uterus, swim up the tubes, and unite with the egg. The early embryo must be able to travel to the uterus through the tubes to implant within the walls of the uterus. The lining of the uterus should be to sustain pregnancy.
After undergoing diagnostic testing, statistics show that 40 percent of fertility issues are female related, 40 percent are male related, 10 percent related to a combination of male and female factors and the remaining 10 percent of fertility issues are unexplained.
The condition is referred to as secondary infertility. Sometimes, a new factor such as infection, can damage the reproductive organs after a child is born, or the natural aging process can make it more difficult for a couple to conceive. The diagnosis and treatment are similar to primary infertility, but often, the prognosis is better.
According to national data there is no major increase in proportion of couples who are infertile. However, many more women are seeking medical services for diagnosis and treatment of infertility. Often, these women seeking treatment have not previously had children.
In general, fertility in women begins to decline after age 30, with a steep drop in fertility rates between the ages of 35 and 45. Miscarriages are also more common among women who are pregnant after the age of 35.